The invention relates to a device and method for impregnating elongate elements with a thermostabilizable substance.
More particularly, the present invention provides an improvement to the device and method for impregnating elongate elements, such as threads or resistant fabrics, reinforced by means of a thermosetting substance, such as a thermosetting liquid resin.
By thermostabilizable substance is meant all substances whose characteristics are durably and permanently modifed under the action of heat and/or temperature.
This thermal action may the sole action responsable for the process of modification of the characteristics of the substance, as may occur during cross linking or vulcanization of the material. This thermal action may also be not the only action to produce durable or permanent modifications of the material, but may act concurrently with other actions, such as oxidation or evaporation of the material, or of a part thereof.
The thermostabilizable substances which may be used by the invention are preferably, but not necessarily, fluid at the different temperatures imposed on the substance in the device, or following the method, of the invention. These substances may for example be thermosetting materials, elastomers, thermoplastics or metals.
The elongate element may be elongate reinforcement elements, such as reinforcing threads made from metal, polyamide, KEVLAR which is a polyaramide whose trademark is registered by the firm Dupont de Nemours, glass, carbon, disposed in layers of parallel threads, braids or fabrics.
In the prior art, when it is desired to impregnate elongate elements, a tank is used having heat regulation means, for example heating means, in which the impregnation substance is disposed and into which penetrates a drum transferring the substance to the zone for impregnation of the elongate elements. A radiating panel generally provides complementary heating of the substance at the impregnation zone level.
Relatively to the prior art, the present invention makes it possible to improve the impregnation quality of the elongate elements, particularly in so far as the deeper penetration of the substance and reduction of air bubble inclusions are concerned, to increase the production rate and finally to considerably restrict material waste, in particular of the thermostabilizable substance.
Moreover, the device and method of the present invention make it possible in numerous cases to reduce and even to omit the addition of solvent to the thermostabilizable substances.
So the present invention, by omitting the addition of solvent, makes it possible to get out solvent elimination means which are generally used upstream the impregnation device according to the prior art.
The flexibility of implementation of the present invention makes it possible to insert the proposed device in a continuous or discontinuous production line, particularly when stoppages thereof are possible.